There is no doubt that the migration of Ethernet from the office domain down onto the plant floor is gathering momentum. Now we are moving towards a scenario where, as well as carrying data, Industrial Ethernet can carry the control information, creating a networking backbone for demanding real-time control applications and safety systems. This article emphasises the fact that increased reliance on Ethernet on the plant floor opens up new security risks, and the protection of sensitive automation networks has become of paramount importance. It states that this is now recognised by automation vendors and automation users alike and, in response to demand, real security solutions are coming to the fore.